Administration of the MapR Database is done primarily via the command line (maprcli) or with the MapR Control System (MCS). Regardless of whether the MapR Database table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter
options. MapR Database administration is associated with tables, columns and column families, and table regions.

The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight
client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify
configuration settings, and how to administer and manage the service.

Configuring Bin Size

The number of bins used by the disk balancer is not constant and is determined by
the sizes of different bins. You can configure the size of each of the bins (Below
Average, Average, Above Average, and Overused) individually at run time. The larger
the size of the bins, the greater the chance that two SPs that are in the vicinity of
each other with respect to utilization fall in the same bin.

The default size of overused bins is only 3%, because SPs in this bin must be balanced at a
finer granularity. The default size of above average, average, and below average bins is 20%.
You can aggressively balance the storage pools across bins by reducing the size of each bin,
forcing the SPs to fall into different bins. To reduce the size of each bin, specify the value
for the following parameters using the maprcli config save command:

Parameter

Description

dbal.above.avg.bin.size

Specifies the bin size (%) of SPs whose usage is above the cluster
average. The default is 20%.

dbal.avg.bin.size

Specifies the bin size (%) of SPs whose usage is in the average range.
The default is 20%.

dbal.below.avg.bin.size

Specifies the bin size (%) of SPs whose usage is below the cluster
average. The default is 20%.

dbal.overused.bin.size

Specifies the bin size (%) of SPs whose usage is in the overused range.
The default is 3%.

For example, to reduce the size of the Below Average bin to 10%, run the following
command: